The poll found that Trump was the top choice of 33% of Republican
primary voters.

That gave him a 13-point lead over the No. 2. Republican, Sen.
Ted Cruz (R-Texas), who had 20% support.

NBC News reported that Trump's margin over Cruz sharply increased
since last month, when the same poll found five points separating
the two candidates.

In the survey released Thursday, Sen. Marco Rubio (R-Florida) was
the first choice of 13% of primary voters, followed by retired
neurosurgeon Ben Carson's 12%. Former Florida Gov. Jeb Bush (R)
and New Jersey Gov. Chris Christie (R) both had 5%, while no
other candidate had more than 3%.

Although Trump is dominant in national polls, the first state to
weigh in on the primary, Iowa, is not as friendly turf for the
real-estate mogul. Cruz has placed first in a number of recent
surveys of likely Iowa caucus-goers, who cast their votes on
February 1.